I always trim to fit the chamber of the gun. I don't really care about posted trim lengths if my gun's chamber accepts longer. I try an un-trimmed case in the chamber, and trim it until it fits. Then trim all the rest to match that length.

40_Rod wrote on Nov 2^nd, 2017 at 10:19am:


I do also if they are high pressure loads. I've never had to trim my old rimmed cases a 2nd time. They don't seem to grow at the pressures and velocities I load them.

....you're right; I should have known better 


westerner wrote on Nov 2^nd, 2017 at 10:52am:

Most are chambered using ( SAMII ) specs. and one should probably use those guidlines if so done and well they are very published and easily found. It is typicaly those that have per-say been wildcated that can indeed benefit from a chamber cast. A chamber cast can be invaluable in a multitude of ways and well beyond just determining a trim to lentgh and something I would highly recommended in either case. And it will provide you with the correct answer to your question the one it provides you and where the others can't.

JLouis